Check out the bottom of my post on June 30th World Record O-Cell Load Test for some updates and new links to recent news articles.
Robert made a presentation at the recent Alabama Section ASCE 2010 Summer Meeting on our participation in some pile load tests on a couple of the storm protection projects in New Orleans (see previous post here). DBA worked for Kiewit Engineering Company (KECo) and the two joint ventures on the projects, providing geotechnical consulting. We are collaborating with KECo on a couple of papers (maybe more) that include the test data. This presentation covered the basics of the test pile programs, highlighted some of the results, discussed the measured setup values for the piles (driven in the soft Louisiana clays), and looked at some comparisons of the dynamic and static load test results to the pile resistance predictions made by DBA during the course of our work. Please note that the Corps of Engineers (and their consultants) were the design engineers. Our work was in support of the contractor joint ventures, especially evaluating pile drivability and installation issues.
Some of the photos included in the presentation were obtained from the public Flickr albums posted by Team New Orleans, U.S. Army Corps of Engineers. There are a lot of good photos there of many of the ongoing projects around New Orleans, as well as an album of historical photos.
You can check out several webcams at the West Closure project here.
You can see Robert’s presentation here.
UPDATE (11/1/10): I have replaced this presentation with a similar one presented at the STGEC 2010 conference in October. The link now directs to the more recent presentation.
Although I have known for several weeks that the manual was finished (I work for one of the authors, after all!), I was waiting for the FHWA to post the link for the new manual before posting this…and now it is here! My friend, Randy Post, has an outside review (meaning not connected to one of the authors!) over at his blog Geoprac.net. Not only did he get “the scoop” on me, but he covers some of the highlights of the “what’s new” with the new, fully revised manual. The biggest change is completely re-writing the design sections to follow LRFD as well as to update the methods for calculating soil and rock resistance. As Randy also notes, the manual has been given a Geotechnical Engineering Circular (GEC) designation: GEC 10. Make sure and go read his review, as well as check out the other things on his blog (disclosure by Robert: I am an occasional contributor there).
The manual’s authors are three of the country’s top experts in drilled shaft design and construction: our own Dan A. Brown, Ph.D, P.E. , John P. Turner, Ph.D, P.E. of the University of Wyoming, and Raymond J. Castelli, P.E. of Parsons Brinckerhoff. As with any major FHWA publication such as this, there was significant industry involvement in the review process through various technical committees and individuals from ADSC, DFI, and Geo-Institute. A note from Dan:
The completion of this manual is a great relief and satisfaction. Many thanks to John Turner’s hard work and also for Ray Castelli’s diligent work to review and make us better. Special thanks to PB Project Manager Jeremy Hung and our FHWA sponsor Silas Nichols for their dedicated efforts to help get this done, and to all of you who contributed.
Dan and John have been using the material in the NHI course this fiscal year, having done some pilot courses the previous year. Some NHI courses, including the Drilled Shaft course, can be hosted by non-government groups. There are also some public seats available occasionally at DOT hosted courses. The NHI catalog page for this course is here.
Also linked on our Publications page.
Update (7/12/10): For those that prefer the feel of a printed volume in their hands, the ADSC: The International Association of Foundation Drilling will be the distributor of the printed volume of the manual through their Technical Library. It will be available soon, according to ADSC. We’ll post about it as soon as it is available.
Update 2 (8/19/10): The printed manual is now available.
DBA was part of foundation engineering and construction history while participating in a drilled shaft load test for the New I-70 Mississippi River Bridge in St. Louis, Missouri. A new O-cell world record of 36,000 tons (bi-directional) was achieved on the test, besting the former record of just under 32,000 tons set in 2005 in Korea (see here).
The test shaft was built by MTA (a joint venture of Massman/Traylor Brothers/Alberici Constructors) as part of an Alternative Technical Concept (ATC) that MTA submitted in their winning bid. During the bid phase, the owner allowed ATC’s to be submitted by pre-qualified teams. These ATC’s were unique to the team that submitted them (e.g., each team was allowed to submit their own ATC’s if they desired, but the ATC’s were not shared amongst all the teams). DBA worked with MTA to develop an ATC that optimized the drilled shaft foundations shown in the “baseline” drawings provided by the owner. That ATC provided a more economical foundation solution that was accepted, bid, and awarded (note MTA also had the option of bidding the “baseline” drawings as-is). A full-scale load test on a dedicated test shaft using the Osterberg Cell (O-cell) test method was included in the ATC to: 1) prove the design values used for the resistance in the rock socket; and (2) take advantage of higher resistance factors for using a load tests as opposed to only calculations. The baseline drawings did not include a load test.
Loadtest, Inc. performed the load test. The bottom-up static load test applied slightly greater than 36,000 tons (bi-directional) to the shaft resulting in about 1/8in of upward movement of the shaft and about the same magnitude of downward displacement at the base. The rock socket was about 23ft deep and 11ft in diameter in very hard limestone. Four 34in O-cells placed at the base of the shaft were loaded to 150% of their rated capacity to achieve the record load.
UPDATE (8/4/10): The bridge was featured in the July 2010 issue of Civil Engineering magazine from ASCE in the “News” section. Follow the link below and then go to Page 30.
UPDATE (8/17/10): Press Release from MTA (contractor joint venture).
UPDATE (8/18/10): ENR.com Article
I have added a recent paper that Dan and Steve contributed to concerning loess that is in the November, 2009 issue of the DFI Journal. The paper describes the results of site investigation and laboratory tests at a site in Kansas with loess deposits. The effectiveness of various correlations between field and laboratory tests and design properties are evaluated. Steve is currently working on the follow-up paper that evaluates lateral load tests of drilled shafts at the site.
Parson, R.L., Johnson, R.M., Brown, D.A., Dapp, S.D., and Brennan, J.J., 2009. “Characterization of Loess for Deep Foundations”, DFI Journal Volume 3, No. 2, November 2009, Deep Foundations Institute, pp14-24.
One area of work we are frequently involved in is data analysis and evaluation of lateral load tests performed by the Statnamic testing device (learn more at the website of Applied Foundation Testing). The mathematics involved in the data reduction can be quite formidable as you interpret the dynamic load-response to an equivalent static load-response. Regardless of the math behind it, watching a test can be pretty cool. It is a whole lot of work for a brief moment of load, but in some situations it can be more economical than a traditional load test.
The video below is from a test on 170-foot long, 32-inch outside diameter steel pipe pile with 0.75"-inch wall thickness. The pile was filled with concrete that included an instrumented rebar cage.
Yes, you read that right – the last drilled shaft has been installed on the John James Audubon Bridge near New Road, Louisiana. The project has been quite an adventure for us, especially Steve. He spent the most time on the site during shaft excavation, tip grouting, load testing, and even pile driving. Robert got to spend a fair amount of time, too, over the last couple of years. Paul was even lucky enough to make a couple of trips.
The shaft construction was concluded with one last O-cell test on Shaft 3W South. Dan was present for the last load test which went fabulously well.
If you are going to the Geo-Institute congress GeoForida 2010 next February in West Palm Beach, you can hear Steve present the paper he and Dan wrote on the tip grouting and load test program.
The bridge is still under construction, of course, and will be an awesome structure when completed. It was an exciting project for us to be a part of the team. We’ll have a project summary posted in the near future to highlight the details of the foundations. For now, you will have to be satisfied with the slideshows below (in reverse chronological order) from some of our visits this summer and fall.
Load Test at Shaft 3W South – October 2009
Excavation of Shaft 3W South – September 2009
Shaft Grouting and other Construction – June 2009
Shaft Excavation, Pile Driving, and Cofferdams – May 2009
I have added the paper that we wrote and Dan presented at the Deep Foundations Institute 34th Annual Conference on Deep Foundations that was held in Kansas City, MO late last month. The paper highlights how the design-build process was successful in the design and construction of the large diameter drilled shafts supporting the bridge. We discuss the installation methods used, the load test program, and how we evaluated the durability of the shale rock sockets under drilling fluid.
Axtell, P.J., Thompson, W.R., and Brown, D.A., 2009. “Drilled Shaft Foundations for the kcICON Missouri River Bridge”, Deep Foundations Institute 34th Annual Conference on Deep Foundations, Conference Proceedings 2009, October 21-23, 2009, Kansas City, Missouri, pp. 3-12.
Who says we only work on drilled shafts?? Robert had the opportunity to work for Kiewit Engineering Company providing geotechnical engineering support to Gulf Intracoastal Constructors (GIC), a joint venture of Kiewit and Traylor Brothers on the Gulf Intracoastal Waterway West Closure Project near Belle Chase, Louisiana. The project is part of the overall flood protection system improvements that are supposed to protect New Orleans from future hurricanes. The key components of this particular project are a massive gate and pump station across the Gulf Intracoastal Waterway. Go For more information on the project, go here, here, and here (video from Corps of Engineers).
Robert spent a good part of the summer in New Orleans doing a variety of geotechnical engineering tasks to support the construction efforts of GIC. The main thing he worked on was the test pile program. The project included a massive test pile program with 24 test piles spread among 5 test sites with various combinations of dynamic, static axial, static tension, and static lateral tests. The piles were mostly open-ended steel pipe piles varying from 18” to 54” in diameter. A few 18” x 18” pre-stressed precast concrete piles were also thrown in for good measure. In addition to performing drivability studies and evaluating tests data, Robert got to spend some time in the wonderful June and July weather in southern Louisiana on the site observing pile installation and testing. And as always, he came back with a lot of pictures. Here are a few to enjoy.
If you frequent this blog, you have noticed that posts have been rare the last few months. That is mostly to my being in the field a lot this summer and very busy on lost of projects. While that is good, it meant I did not have time for updates. Below are some slide shows from a few drilled shaft projects we worked on this summer.
Garden State Parkway Mullica River Bridge, New Jersey – Test Shaft Installation
Paul took a trip to lovely New Jersey to observe a large diameter test shaft on the Mullica River Bridge. DBA worked as a consultant for Parsons Brinckerhoff on an 8-foot diameter, 220-foot deep test shaft. CASE was the drilled shaft contractor and Agate was the general contractor. DBA consulted on the design of the test shaft program, as well as the use of Self Consolidating Concrete (SCC).
Drilled Shaft Lateral Load Test Research with the University of Kansas
Paul took a ride out west to Kansas City, Kansas (close to home!) to observe a drilled shaft lateral load test in Wyandotte County, near the Cabela’s store on I-435. The test is part of ongoing research by the University of Kansas for the Kansas DOT. DBA was involved in previous research concerning laterally loaded shafts behind MSE walls (see previous post, click here for more information on the project). This research continues on the same theme of investigating the behavior of laterally loaded shafts socketed into the sedimentary rocks in eastern Kansas. DBA does not have an active role in this project, just an academic interest.
Huey P. Long Bridge Improvements, New Orleans, Louisiana – Test Shaft Installation
The Huey P. Long Bridge in New Orleans (built in the 1930s) is undergoing a major rehab and expansion. The vehicle traffic will increase from 2 9-foot lanes in each direction to 3 11-foot lanes in each direction. This is a very interesting combined highway and railroad bridge with a fascinating history. The bridge is actually a private bridge owned by the New Orleans Public Belt Railway (click the link to see some cool photos from the construction of the bridge in the 1930s). The project website is here.
DBA was consulting with the joint venture building the bridge for the base-grouted drilled shafts under one new pier. A test-shaft was built and tested with O-cells. Robert was on site while they excavated the test shaft. Steve was on site during grouting.